"Belfast Mill" is a version of "Aragon Mill," written by Si Kahn, published by Joe Hill Music, HFA Song Code: A73060.

You can find a lot of these publishers (and license them) at the Harry Fox Agency Website, http://www.harryfox.com - then go to their "songfile" section. I've found their licensing procedure to be quite easy, but it bugs me to have to pay a corporation a license fee on a song that's half a century old, with the songwriter long dead (the Si Kahn song doesn't fit that, and Si justly deserves his royalties).